I see no reason why a soul-suck wouldn't work either.
Physically, Sentry obviously has an edge, though not a huge one in his "normal" incarnation. I'd tend to think it wouldn't be impossible for Adam to win in such a regular confrontation, just unlikely.
I actually think that Adam Warlock has a good chance of winning considering his karmic blast and superior h2h fighting skills which will allow him to press the battle ...
I think Sentry would win the majority but it would not be easy. Warlock is a very crafty hand to hand fighter, and I would think his karmic blasts and soul attacks would be effective against someone as unstable as Bob.
Nice match-up.
I'm just gonna watch for now. But, my thoughts are that Sentry is a serious powerhouse, while Adam has some nice tricks and has been shown to be pretty dangerous.
It would be interesting to see how the SG would affect Sentry. Sending him to SW would be bfr, but isn't there still the possibility that the gem could be used to f*ck with Bob, possibly even make him fight himself like Ed Norton in Fight Club?